Bituminous materials and the method of preparing the same



Patented Nov. 3, 1953 BITUMINOUS MATERIALS AND THE METH- OD OF PREPARINGTHE SAME Frederick H. MacLaren, Munster, Ind., and Mathew L. Kalinowski,Chicago, Ill., assignors to Standard Oil Company, Chicago, 111., acorporation of Indiana N Drawing. Application June 27, 1951, Serial No.233,946

Claims. (Cl. 19622) This invention relates to improved homogeneousbituminous materials and to the method of obtaining the same, and morespecifically the invention pertains to homogeneous bituminous materials,e. g., asphalts, having a negative spot test, and to the method ofobtaining the same from a bituminous material normally having a positivespot test.

Bituminous materials, such as asphalts, cutback asphalts and road oilresiduums, used in the construction of asphaltic roadways and for otherpurposes are frequently required to pass a test which is indicative ofthe homogeneity of the product used. This test, popularly known as thespot test, is often referred to as the Oliensis test and less frequentlya the homogeneity test. This test (fully described in the A. S. T. M.Proceedings, volume 33, part II [1933], A. S. T. M. Proceedings, volume36, part II [1936] in Abraham Asphalts and Allied Substances, page 782[Test 2D], and in American Association State Highway Oificials, StandardSpecifications for Highway Materials and Method of Sampling and Testing,part II, Designation T102-42 [1942]) is carried out in the followingmanner: Two grams of the bituminous materials to be tested are placed ina flask and dissolved in 10.2 cc. of a special naphtha, designated SpotTest Naphtha, meeting the following requirements:

A. P. I. gravity 49-50. Initial boiling point Not less than 300 F. 50%distillation point 335 F. to 355 F. End point Not over 410 F. Anilinenumber (A. S. T. M.

91-33) 59 C. to 63 C.

The flask and contents may be warmed and when the sample appears to bedissolved, the flask is set aside for thirty minutes and permitted tocool to room temperature. The contents of the flask are mixed byvigorously swirling the flask and three drops of the solution placed ona clean Whatman filter paper, care being taken that the spots do not runtogether. After five minutes, the spots are examined in a good difiusedlight. If the drops form a brown or yellowish circular stain with adarker solid or annular nucleus in thecenter, the spot .test is reportedas positive and the solution in the flask is discarded. However, if thedrops form a uniformly brown circular stain, it is reported as negativeand the filter paper preserved for subsequent comparative test purposes.The flask containing the solution of bituminous materials being testedis stoppered and set aside out of strong light for a period oftwenty-four hours. At the end of this period the solution is again mixedand stirred with aclean glass rod. Three more drops of the solution arethen placed on the filter paper previously used, and after five minutes,examined. If the drops from the twenty-four hour old solution still forma uniformly brown circular stain, the spot test is said to be negative.However, if the drops form a brown or yellowish brown circular stainwith a darker solid or an annular nucleus, the spot test is reported aspositive. In order to meet specifications, the bituminous material beingtested must show a negative spot test. At times the bituminous materialhaving a negative spot test will be referred to and classified ashomogeneous While the product which has a positive spot test will bereferred to and classified as heterogeneous.

It is an object of the present invention to pro-' vide a bituminouscomposition having a negative spot test. Another object of the inventionis to provide a negative spot test bituminous composition containing abituminous material normally having a positive spot test. A furtherobject of z the invention is to provide a homogeneous asphalt having anegative spot test employing as a major component thereof a bituminousmaterial normally having a positive spot test. A still further object ofthe invention is to provide a methodof correcting heterogeneity inasphaltic materials. Still another object of the invention is to providea method for converting positive spot test asphaltic materials tonegative spot test asphaltic materials. Other objects and advantages ofthe pres-' ent invention will become apparent from the followingdescription thereof. In accordance with the present invention bituminousmaterials,- such as asphalts, cut-back asphalts and other crudepetroleum residuum, which normally exhibit a positive spot test whensubjected to the hereindescribed' test, are con v verted to productswhich will give a negative spot test by the addition of a small butsufficient quantity of the propane-insoluble asphaltic resins obtainedin the propane deasphalting of a reduced crude petroleum oil, normallyhavin a negative spot test. We have found that as little as 0.5%, byweight, of these asphaltic resins will convert a normally positive spottest bituminous material to a negative spot test product. Usually, fromabout 0.5% to about 15% of the propane-insolubleasphaltic resins will befound suflficient for the purpose herein described; although, largerquantitles, such as %.t0 40%, can be used so long as the desiredproperties of the bituminous. mateprocess, well known in the art, is aliquid-liquid I extraction process involving the contacting of thereduced crude oil or residuum with liquefied propane, separating of theresultant propane-oil and the propane-insoluble asphaltic resin phasesand the recovery of the propane therefrom. The

extraction with the liquefied propane may be carried out eitherstagewise or countercurrently. In conventional processes for thedeasphalting of reduced petroleum crude oils a propane to oil chargeratio of from about 1.5 to about 5 parts of propane to each part. of oilcharged is employed, using temperatures in the range of from about 100F. to about 150 F., and pressures within the range of from about 200 toabout 500 pounds per square inch gauge. The process for the deasphaltingof reduced petroleum oils is well known and is described in U. S.Patents Nos. 1,944,491; 1,949,989; 2,041,275; 2,081,473, and others.While liquefied propane is the material usually used in conventionaldeasphalting processes, other lique fied normally gaseous hydrocarbons,such as methane, ethane and butane can be used. We have found that thepropane-insoluble asphaltic resins obtained by the propane deasphaltingfrom any 18% to reduced crude oil can be satisiactorily employed forthe-hereinedescribed invention provided the reduced crude exhibits anegative spot test. The herein described invention, however, is notlimited tov the propane-insoluble asphaltic resins from 18% to 40%reduced crude, but includes the use of asphaltic material from anyprocess in which a liquefied normally gaseous hydrocarbon is employed toprecipitate insoluble asphaltic resins from a reduced crude petroleum ilor petroleum residuums which exhibits a negative spot test.

.The present invention provides a method. for correcting theheterogeneity of any asphalt and/or residuum whereby such materials areconverted from a positive spot test product to a negativespot testproduct. We have found the asphaltic resins of the type herein describedare" effectivein correcting the heterogeneity of any oxidized orunoxidized, asphalt, or residuum, such as for.- example, positive spottest asphalts and residuums from low sulfur Mid-Continent crudeoils. lowsulfur Mid-Continnent-type crude oils, high sulfur West Texas crudeoils, high sulfur Wyoming crude oils, and others.

The effectiveness of asphaltic resins of the type herein describedinconverting positive spot test bitumen materials to negative spot testprod ucts is illustrated by the following examples which are given byway of illustrating the invention, and are not to be construed aslimiting the scope thereof.

EXAMPLE I An asphalt, obtained by reducing 38% West Texas crude oilresiduum to an asphaltic bottoms having a softening point of 100 F. to110 F., exhibited a positive spot test. To portions of this asphalt wereadded 0.5%, 1%, and 2% of propane-insoluble asphaltic resins obtained bypropane deasphalting a 25% reduced bottoms of a Mid-Continent crude oilof low sulfur content. The asphaltic resin had a softening point ofabout 117 F., a penetration at 77 F. of about 65, and a flash (C. O. C.)of about 480 F. Each of the resultant blends exhibited a negative spottest.

EXAIVIPLE II An asphalt having a softening point of F. to F., obtainedby the reduction of a West Texas crude oil of high sulfur content andwhich exhibited a positive. spot test was blended as in Example I with0.5%, 1% and 5% of asphaltic resins of the type used in Example I. Theresults obtained are shown in the following table:

Table I Sample Spot Test West Texas Asphalt Positive. West TexasAsphalt+0.5% Propane-Insoluble Asphaltlc Do.

Resin. West Texas Asphalt+l.0% Propane-Insoluble Asphaltlc Dc.

esin. Wr st Texas Aspha1t+5.0% Propane-Insoluble Asphaltic Nelativn.

esm.

The spot test of this West Texas asphalt was more severely "positivethan that of Example I and therefore required a larger amount of thepropane-insoluble asphaltic resin to convert it to a product having anegative spot test.

EXAMPLE II EXAMPLE IV The residuum of Example III when mixed with 10 ofthe propaneinsoluble asphaltic resin havingthe following inspection gavea product having a negative spot test.

Softening point 174 1.

Penetration at 77 F.. 4.

Flash (C. O. C.) "31",. 580" F.

EXAMPLE V A blend of 85% of a. residuum from a high sulfur Wyoming crudeoil and 15% of a residuum from a Steamboat Butte Tensleep which, had a.

positive spot test was converted to a product having a negative spottest by the addition of 5% of the propane-insoluble asphaltic resin ofthe type used in Example 1V.

EXAMPLE VI Blends consisting of 70% of the Wyoming crude oil residuumand 30% of the Steamboat residuum and blends of 60% of the Wyomingresiduum and 40% of the Steamboat residuum, each showing a positive spottest were converted to products having a negative spot testby theaddition of 10% of the asphaltlc resin 0! Example IV. The

To determine the effectiveness of the present invention in correctingthe spot test of cracked asphalts a continuous pressure still crackedresiduum having an A. P. I. gravity of 7.8", a flash of 340 F., a Furolviscosity at 122 F. of 227 seconds, and a pourpoint of +35 F. andshowing a positive spot test was admixed with various amounts of apropane insoluble asphaltic resin of the type used in Example I. It wasfound that 70% of the propane-insoluble asphaltic resin was required toobtain a negative spot test. While a relatively large amount of theasphaltic resin was required, it is unexpected that a negative spot testcan be obtained at all on an asphalt containing as much as 30% of acracked product since the spot test was originally designed to indicatethe presence of any cracked products in asphaltic materials.

Frequently, petroleum bitumen composition, such as asphalts, cut-backasphalts, road oils, and the like, used for paving and road building,are compounded with various additives, such as anti-stripping agents.Such additives are used to facilitate the application of pavingmaterials and road oils to wet mineral aggregates and to prevent thestripping of such materials from wet aggregates. Examples of suchadditives are metal salts of sulfonic acids, naphthenic acid, highmolecular Weight fatty acids, as well as fats and fatty material, suchas the propane-insoluble residue obtained from the propane fractionationof crude fatty materials. Particularly effective additives are calciumpetroleum sulfonates. In many cases difiiculty is experienced in keepingsuch additives in stable suspension or solution, in the bitumenmaterial. We have found that the addition of up to 35%, by weight, ofthe asphaltic resins insoluble in liquefied normally gaseoushydrocarbons, for example, propane, is very efiective in stabilizingsuch compositions against separation of the anti-stripping agents.

While we have described our invention by reference to specific examplesthereof, these have been by way of illustration only and the inventionis not to be limited thereby but includes Within the scope suchmodifications and variations as come within the spirit of the appendedclaims.

We claim:

1. The method of converting a positive spot test petroleum bitumenmaterial to a negative spot test product, comprising admixing with apetroleum bitumen material normally having a positive spot test, anuntreated asphaltic resin insoluble in a liquefied normally gaseoushydrocarbon obtained from the deasphalting of a petroleum residuumnormally exhibiting a negative spot test with a liquefied normallygaseous hydrocarbon, said untreated asphaltic resin being present in asmall but sufficient quantity to give the resultant product a negativespot test.

2. The method of converting a positive spot test petroleum asphalticmaterial to a negative spot test product, comprising admixing apetroleum asphaltic material normally exhibiting a positive spot testwith an untreated propaneinsoluble asphaltic resin obtained from thepropane deasphalting of a petroleum residuum normally exhibiting anegative spot test, said propane-insoluble asphaltic resin being used insmall but suflicient quantities to impart to said petroleum asphalticmaterial a negative spot test.

3. The method of claim 2 in which the propaneinsoluble asphaltic resinis used in amounts within 6 the range of from about 0.5% to about 15%,by weight.

4. The method of correcting the heterogeneity of a petroleum asphalticmaterial comprising admixing with a petroleum asphaltic materialnormally having a positive spot test, from about 0.5% to about 15%, byweight, of untreated propane-insoluble asphaltic resins obtained in thepropane deasphalting of a petroleum residuum normally exhibiting anegative spot test.

5. The method of preparing a petroleum asphaltic product having anegative spot test comprising admixing a petroleum asphaltic materialnormally having a positive spot test with from about 0.5% to about 15%,by weight, of untreated propane-insoluble asphaltic resins, obtainedfrom petroleum residuums normally having a negative spot test.

6. The method of converting a positive spot test asphalt to a negativespot test asphalt, comprising incorporating in a positive spot testasphalt from about 0.5% to about 15%, by weight, of untreatedpropane-insoluble asphaltic resins obtained by propane deasphalting apetroleum residuum normally having a negative spot test.

7. A petroleum asphaltic composition having a negative spot testcomprising a major proportion of a petroleum asphaltic material normallyhaving a positive spot test and a minor proportion of untreatedasphaltic resins insoluble in liquefied normally gaseous hydrocarbonsobtained from the deasphalting of a bitumen residuum normally having anegative spot test with a liquefied normally gaseous hydrocarbon, saidasphaltic resins being present in small but sufficient quantities toimpart to said composition a negative spot test.

8. A petroleum bitumen composition having a negative spot testcomprising a major proportion of a petroleum bitumen normally having apositive spot test and from about 0.5% to about 15%, by weight, of anuntreated propane-insoluble asphaltic resin obtained in the propanedeasphalting of a bitumen residuum normally having a negative spot test.

9. A petroleum asphalt composition having a negative spot testcomprising a major proportion of a petroleum asphalt normally having apositive spot test and. from 0.5% to about 15%, by weight, of untreatedpropane-insoluble asphaltic resins obtained by the propane deasphaltingof a petroleum residuum normally having a negative spot test.

10. A road oil composition having a negative spot test comprising amajor proportion of a petroleum residuum normally having a positive spottest and from about 0.5% to about 15%, by weight, of an untreatedpropane-insoluble asphaltic resin obtained by the propane deasphaltingof a petroleum residuum normally having a negative spot test.

FREDERICK H. MACLAREN. MATHEW L. KALINOWSKI.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 2,073,088 Anderson et al Mar. 9, 1937 2,131,205 Wells et alSept. 27, 1938 2,220,714 Hersberger Nov. 5, 1940 2,224,372 Anderson Dec.10, 1940 2,317,150 Lovell et a1 Apr. 20, 1943

1. THE METHOD OF CONVERTING A POSITIVE SPOT TEST PETROLEUM BITUMEN MATERIAL TO A NAGATIVE SPOT TEST PRODUCT, COMPRISING ADMIXING WITH A PETROLEUM BUTUMEN MATERIAL NORMALLY HAVING A POSITIVE SPOT TEST, AND UNTREATED ASPHALTIC RESIN INSOLUBLE IN A LIQUEFIED NORMALLY GASEOUS HYDROCARBON OBTAINED FROM THE DEASPHALTING OF A PETROLEUM RESIDUUM NORMALLY EXHIBITING A NEGATIVE SPOT TEST WITH A LIQUEFIED NORMALLY GASEOUS HYDROCARBON, SAID UNTREATED ASPHALTIC RESIN BEING PRESENT IN A SMALL BUT SUFFICIENT QUANTITY TO GIVE THE RESULTANT PRODUCT A NEGATIVE SPOT TEST.
 7. A PETROLEUM ASPHALTIC COMPOSITION A MAJOR PROPORTION NEGATIVE SPOT TEST COMPRISING A MAJOR PROPORTION OF A PETROLEUM ASPHALTIC MATERIAL NORMALLY HAVING A POSITIVE SPOT TEST AND A MINOR PROPORTION OF UNTREATED ASPHALTIC RESINS INSOLUBLE IN LIQUEFIED NORMALLY GASEOUS HYDROCARBONS OBTAINED FROM THE DEASPHATING OF A BITUMEN RESIDUUM NORMALLY HAVING A NEGATIVE SPOT TEST WITH A LUQUFIED NORMALLY GASEOUS HYDROCARBON, SAID ASPHALTIC RESINS BEING PRESENT IN SMALL BUT SUFFICIENT QUANTITIES TO IMPACT TO SAID COMPOSITION A NEGATIVE SPOT TEST. 